The research proposal described herein is aimed at the preparation of ruthenium complexes with novel ligands to effect synethetically useful metathesis reactions. Specifically, efforts will be focused on the stabilization of a methylidene complex for the development of a practical ethenolysis reaction, and the design of a chiral ligand set in order to accomplish enantioselective metathesis reactions. Ethenolysis, the cross metathesis reaction where ethylene is used as the cross-partner, is useful in organic synthesis to dehomologate olefins, and as a degradation tool to determine the structure of natural products. The development of general enantioselective catalysts would further extend applicability of olefin metathesis in organic and polymer chemistries. New carbene ligand architectures will be explored in order to realize these goals. [unreadable] [unreadable] [unreadable]